Coating and method for marking teeth

ABSTRACT

Pressure sensitive coatings are applied to opposing occluding surfaces of teeth. The coating includes a plurality of dispersed cells each of which contains one of two chemically interactive substances. These cells rupture in response to application of occlusal pressure thereto, the substances of the ruptured cells chemically interacting and producing localized stained areas at locations of premature tooth contact between upper and lower teeth.

United States Patent Friedman [451 Nov. 11, 1975 [76] Inventor: Abraham Friedman, 2205 E. 27th St., Brooklyn, NY. 11229 [22] Filed: July 9, 1973 [21] Appl, No.: 377,631

[52] US. Cl. 32/19 [51] Int. Cl. A61C 9/00 [58] Field of Search 32/19; 260/23, 32; 346/135; 106/145, 236, 240

[56] References Cited UNITED STATES PATENTS 2,299,693 10/1942 Green 346/135 X 3,421,223 l/l969 Stark 32/19 3,707,771 l/l973 Guerra 32/19 Primary Examiner-Robert Peshock Assistant E.\'aminer.l. Q. Lever Attorney, Agent, or FirmFriedman & Goodman [5 7] ABSTRACT Pressure sensitive coatings are applied to opposing occluding surfaces of teeth. The coating includes a plurality of dispersed cells each of which contains one of two chemically interactive substances. These cells rupture in response to application of occlusal pressure thereto, the substances of the ruptured cells chemically interacting and producing localized stained areas at locations of premature tooth contact between upper and lower teeth 3 Claims, N0 Drawings COATING AND METHOD FOR MARKING TEETH BACKGROUND OF THE INVENTION The present invention generally relates to dentistry, and more particularly to the means and method of indicating the precise points of premature contact when the teeth are brought together.

Numerous proposals have been made for providing indications of high points on teeth or portions to be removed when the latter interfere with the natural bite of the teeth and, consequently, form premature points of contact therebetween.

A popular method utilized heretofore has been the placing of carbon paper between the teeth. The patient bites on the carbon paper and some of the carbon transfers onto the teeth. However, this method frequently does not bring about the natural closing of the mouth, both for physical as well as psychological reasons. The presence of a section of carbon, having a finite thickness between the teeth, prevents the bite to assume a natural form. Also, a patient is frequently reluctant or uncertain as to the manner in which to bring his teeth together.

Another method utilized heretofore has been the use of a relatively thick strip of wax or other impressionable material which could be deformed by the occlusal surfaces during a bite; However, the use of such materials has not always resulted in readily interpretable or accurately definitive data of the precise contact point locations sought to be determined.

Also known in the prior art is a transfer pad which is provided with two opposing outer layers each saturated by another of two chemically interactive materials. The two opposing layers are separated by an intervening barrier layer which separates the chemically active materials before and during the articulation test. However, this pad has had the drawback above described with carbonized marking sheets insofar as accurate measurements are concerned. Further, the transfer pads of the type under discussion first require that the pad be placed between opposing occluding surfaces of interest and biting the pad to transfer another one of the chemicallyinteractive materials to an opposing occlusal surface. The procedure then requires that a further bite be taken at which time the prematurely contacting occlusal surface points engage, thereby intermixing the two chemically active materials to provide a visible indication of the high points to be removed. Clearly, the transfer pad method requires two bites for each indication. This may be time consuming and inconvenient when numerous articulation tests are to be performed.

Still another means for detecting dental occlusions which has been proposed has been the provision of a powder, such as calcium carbonate, in a propellant such as freon. A thin film of the powder is spread onto the occlusive surfaces and permitted to dry. Biting of the teeth breaks the film, this providing an indication of the areas of occlusion after the mouth is naturally closed. A disadvantage of this procedure is that the film is sprayed onto the teeth and, consequently, into the mouth. Also, because the indications result from breakages in the film by forcefully biting the teeth, errors may arise since the bite is not a natural one and the upper and lower teeth may slip one relative to the other during the biting process.

SUMMARY OF THE INVENTION It is an object of the present invention to provide means for marking tooth contact points on occlusion which does not possess the disadvantages described above in connection with prior art comparable means.

It is another object of the present invention to provide tooth marking means of the type under discussion which is simple and economical to produce.

It is still another object of the present invention to provide tooth marking means of the type above described which is simple to utilize.

It is yet another object of the present invention to provide tooth marking means which provides indications of precise localized areas where premature tooth contact takes place.

It is a further object of the present invention to provide tooth marking means which has virtually no thickness to thereby minimize the errors inherent in prior art articulation tests.

It is still a further object of the present invention to provide tooth marking means which require but a single bite to provide an accurate indication of high points on occlusal surfaces.

It is yet a further object of the present invention to provide a method of utilizing the above described tooth marking means.

To achieve the above objects, as well as other objects which will become apparent hereafter, means for marking tooth contact points in occlusion comprise a pressure sensitive coating applied to at least one of two 0pposing occluding teeth. The coating includes a plurality of dispersed cells each containing one'of two chemically interactive substances. The cells are rupturable in response to application of occlusal pressure thereto. In this manner, the substances of the ruptured cells chemically interact and produce localized stained areas indications of premature tooth contact points between upper and lower teeth.

According to one presently preferred embodiment, said coating comprises a continuous phase including an emulsion of cells of said interactive substances. According to another presently preferred embodiment, said coating comprises a binder material and a dispersion of a plurality of microcapsules each containing one of said interactive substances. Each micro-capsule includes a thin substantially spherical rupturable wall.

The continuous phase or the binder material of the coating is advantageously but not necessarily in a rapidly drying liquid or paste form.

The method of the present invention comprises the step of applying the above described pressure sensitive coating to at least one of two opposing occluding teeth. Advantageously, the coating is applied to both opposing occlusal surfaces.

Where the coating is in a rapidly drying liquid form. the method further comprises the step of waiting after the applying step until the coating has substantially dried before causing the occluding surfaces to come into contact with each other in pressure relation.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The means for marking the tooth contacts on occlusion thereof in accordance with the present invention comprises a pressure sensitive coating applied to at least one of two opposing occluding teeth.

The coating includes a plurality of dispersed cells each containing one of two chemically interactive substances. The cells are rupturable in response to application of occlusal pressure thereto. In this manner, the substances of the ruptured cells chemically interact and produce localized stained areas at locations of prematured tooth contact points between upper and lower teeth.

The precise nature of the coating or of the chemically interactive substances is not critical for the purpose of the present invention. The interactive substances are selected to produce, on intermixture, a color which is readily distinguishable from the overall color of the coating.

According to one presently preferred embodiment, the coating comprises a continuous phase including an emulsion of cells of the interactive substances. An example of such a coating is described in U.S. Pat. No. 2,299,693, wherein the coating is described in conjunction with paper. The pressure sensitive emulsion there described is applied to the paper and dried thereon. The dried coating has profusely dispersed at random therein minute, liquid-containing cells of two types, which two types of liquid are kept chemically insulated one from the other until the coating is ruptured in selected areas by impact or pressure. At such time, the liquid contents of the two types of cells are caused to contact and chemically unite with one another to form a localized stained area.

Several examples are provided in the above refer- I enced patent of specific chemical designations for the continuous phase or coating as well as for the chemical compositions of the chemically interactive materials. According to one example, the dispersed liquid cells of the first emulsion contain gallic acid and the dispersed liquid cells of the second emulsion contain ferric ammonium sulphate. Upon rupture of the cells, the generially blue-black color changes to a black color.

Another class of chemically interactive materials which can be utilized are Ph indicators and the materials which react with the same. For example, an acidbase indicator such a phenophthalein may be utilized as one of the interactive materials and the other material may be, for example, sodium-tetraborate. Further examples of possible materials which may be utilized are set forth in the above referenced U.S. Patent, as well as in the patents which are listed below.

In the selection of the interactive materials, consideration should be given to the possible toxicity of the materials when used in the minute quantites contemplated. It is pointed out that the present invention contemplates the application of the coating in localized areas, not sprayed into the mouth, as suggested in the prior art. For this reason, the quantity and regions of local application of the coating can be limited.

According to another presently preferred embodiment of the coating, a plurality of micro-capsules are dispersed in a carrier, binder or matrix material. With this embodiment, the micro-capsules each contain one of the interactive chemical substances. Here, each micro-capsule comprises a thin substantially spherical rupturable wall which breaks and empties the contents thereof upon rupture.

The term mirco-capsule as herein employed is intended to designate a minute or microscropic capsule wherein a nucleous or microscropic drop of liquid material is surrounded by a mantle of relatively impervious material. The mantle is relatively thin and pressure 4 rupturable. Micro-capsules of the type to which reference is here made have formed by coacervation as well by method involving intcrfacial polycondcnsation. Reference in this connection is made to the following United States Letters Patent.

Re. 24.899 Nov. 29. 1960 B. K. Green 2.299.693 Oct. 20. I942 B. K. Green 2,374,862 May I. I945 B. K. (irecn 2.730.456 .lan. l0. I956 B. K. Green et all 2,730,457 Jan. l0. I956 B. K. (irccn ct al 2,800,457 July 23. I957 B. K. Green et al 2.800.458 July 23. I957 B. K. (ireen 2.953.470 Sept. 20. I960 B. K. (ireen ct al 2,971.9l6 Feb. [4. l96| L. Schlciclier et al 2.988.46l June l3. l96l HQ]. Eichel 3.016.308 Jan. 9. I962 N. Macaulay 3,069,370 Dec. IX. I962 E. H. Jensen et al A description of the 'interfacial polycondensation:

colors which are introduced into the mouthfand onto I the teeth are the colors produced by the chemically interactive agents at the high points of the occlusal surfaces. Also, the carrier material is advantageously easily washed off the teeth after being applied thereto. In this manner, numerous articulation tests may be performed in rapid successionwithout the occurrence of,

errors due to the presence of previously applied coatings. One example of a suitable carrier includes a starch mixture in which the micro-capsules are dispersed.

The method of utilizing the coatings above described 1 involves applying the coating to at least one of two opposing occluding surfaces. Advantageously, the coating is applied to both occluding surfaces. It is possible. to

select the binder or carrier material to be in a rapidly] drying liquid form. With such a coating, the latter is applied to the occlusal surfaces in any suitable manner. such as, with a brush, and'permitted to dry. Upon drying, the layer of the coating produces a dried film in i which the micro-capsules are dispersed. Clearly, the

resulting film is infinitesimal in thickness and does not interfere with the natural bite of the patient.

The above coating for conducting dental articulation tests is simple to apply and provides accurate locations of occlusal high points.

Numerous alterations of the structure herein dis closed will suggest themselves to those skilled in the art. However, it is to be understood that the present disclosure relates to a preferred embodiment of the invention which is for purposes of illustration only and is not to be construed as a limitation of the invention.

What is claimed is:

1. Method of marking tooth contact points on occlusion, comprising the step of applying a pressure sensitive coating to at least one of two opposing occluding teeth, said coating including a plurality of dispersed cells each containing a one of two chemically interactive substances, said cells being rupturable in response to application of occlusal pressure thereto, whereby the substances of the ruptured cells chemically interact and produce localized stained areas at locations of premature tooth contact points between upper and lower Method M P "F p i points as q F "1 claim 1, wherein the coating is in a rapidly drying liqlcclhuid form, the method of further comprising the step of 2. Method of marking tooth contact points as defined waiting after the pp Step until the Coating has stantially dried before causing the occluding surfaces to come into contact with each other in pressure relation. posing ocelusal surfaces of the teeth.

in claim 1, wherein the coating is applied to both op- 5 

1. Method of marking tooth contact points on occlusion, comprising the step of applying a pressure sensitive coating to at least one of two opposing occluding teeth, said coating including a plurality of dispersed cells each containing a one of two chemically interactive substances, said cells being rupturable in response to application of occlusal pressure thereto, whereby the substances of the ruptured cells chemically interact and produce localized stained areas at locations of premature tooth contact points between upper and lower teeth.
 2. Method of marking tooth contact points as defined in claim 1, wherein the coating is applied to both opposing occlusal surfaces of the teeth.
 3. Method of marking tooth contact points as defined in claim 1, wherein the coating is in a rapidly drying liquid form, the method of further comprising the step of waiting after the applying step until the coating has substantially dried before causing the occluding surfaces to come into contact with each other in pressure relation. 